Apparatus for the balancing of rotatable bodies.



J. F. METTEN. APPARATUS FOR THE BALANCING 0F ROTATABLE BODIES;

APPLICATION FILED MAR.12,1909. 1,047,677; Patented Dec. 17, 1912.

2 SHEETS-SHEBT 1,

J. F. METTEN.

APPARATUS FDR THE BALANCING OP ROTATABLE BODIES.

APPLICATION FILED MAR. 12, 1909.

Patented Dec. 17, 1912.

q Vih teo as Z- i MM UNIT STATES "PATEN r OFFICE.

JOHN NI ETT I ZN, O3E"PHIL,ADELPHIA, PENNSYLVANIA, ASSIGNOB T I'M. GRAFH? & SONS SHIIE & ENGINE BUILDING COMPANY, A*CORPOBAATION OF PENNSYLVANIA.

To all whorh it may concern Be it known that 1, JOHN- F. Mn'r'rEN, a citizen of the United. States, residing at Philadelphia, in the county of- Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Apparatus; for the Balancing of Rotatable Bodies, of whiclrthe,followlng 1s a full, clear, and exact specification.

9 This invention relates to apparatus for the balancing of rotatable bOCllGS, and more particularly has reference to apparatus for determining the amount and location of weights necessary to be added or removed in order to dynamically balance the rotors for-elastic fluid turbines.

The rotors of elastic fluid turbines are commonly built up of a large number of bucket wheels, fixed on the shaft, which may vary in diamcteraccording to their position. When such a rotor carrying dissimilar elements is assembled, it necessary that is should be balanced, so as to rotate at high speeds without vibration, and 1f not, to

change the disposition of. weight so that it will rotate perfectly true without any oscillation at high speeds.

It is the object of this invention to provide apparatus whereby the balance of a 39 turbine rotor may be determined readily and cheaply without the necessity of mounting the rotor in the casing and running it iinder steam pressure experimentally a number of times before the balance is determined. This object I attain by the apparatus hereinafter described, consisting in mounting the rotor to be balanced n a balancing apparatus comprising bearing sup ports arranged to have a limited degree of movement, and mechanically driving the rotor by a motor at such speeds as to cause vibration of the rotor in the movable supports if the rotor is not balanced. By marking the rotor or the shaft at points of cc- 5 centricity, disposition of weights can be varied according to these markings until the vibrations are eliminated and the rotor runs perfectly true at any speed. By this method, a rotor can be accuratelybalancedbefore it is put in the casing, and without driving it by steam, thereby avoidin the --trouble and expense of'mounting an dismounting the rotor in the casingwhile adjusting its balance and also enabling a more accurate balance to be obtained.

APPARATUS FOR THE BALANCING 0F ROTATABLE BODIES.:

In the accompanying'drawings, form-10f apparatus embodying the invention is shown, wherein, 7

Figure l is a plan view of an apparatus embodying the invention, Fig. 2 isan end view, Fig. 3 is a side elevation, on anenlarged scale, of one of the movablerotor bearings, and Fig. 4 is an elevation, partly in section, on the line of Fig. 3,'of one of the rotor bearings. v

1, 1, represent generally U-shapedupright supports adapted to be secured to afloor, and pivoted thereon at 2 is an upwardly extending hanger'3 carrying at its other end a bearing 4 adapted tojreceive the rotor shaft, which is-held therein by an upper cap 6 reinovably secured thereto by bolts 7. The hanger 3 preferably is guided by bridge pieces 8 carried by the uprights 1, so as to preventlongitudinal swaying of the rotor shaft. 9 is the rotor proper. The hanger 3 is provided with a projecting rib or lug 10, and interposed between this lug 10, and theends 11 of the supports, are resilient cushions 12 which are preferably provided with bearing plates 13 engaged by screws 1 1 threaded into the supports 1. By this means the amount of resistance the cushions 12 will offer to vibration of the shaft hanger 3 will be controlled. A similar provision is'made for each end of the rotor shaft 5, andat one end is coupled by coupling 17, a somewhat flexible driving shaft 18 supported in a bearing 19 and having a driving pulley 20, which is driven throughla belt- 21 from an electric motor 22, controlled in any suitable manner to go in either direction.

24 is a bracket mounted adjacent therotor and carrying a pencil or other Inarkingdevice25 adjustable toward and from thejpe ripliery of the rotor so as to make .a :inark thereon when brought into. contact. Several of these may be used disposed at different points along the rotor, if desiredii 27 represents a bracket on which 2x11730117 tor 11th.

Section in Letters Patent No. 1,047,677.

shaft is marked at points of eccentricity.

The point upon the shaft at which the mark is made at ordinary speeds is approximately in the radius containing the excess Weight which causes the vibration. The unbalanced portion having" been thus determined, it.

will be apparent that the condition of balance may be approached by removing Weight from the rotor upon the side of the axis Where the mark is located, or by increasing the weight upon the opposite side, either operation tending to "shift the dynamic center of mass closer to the axis of rotation. \Vhen they are coincident balance is of course attained. W eight having been added or subtracted as described, the rotor is again rotated in the movable supports and any vibration produced is availed of as before described tor securing another indication of where weight should be added or removed. This operation is repeated until no vibration, or one within'permissible limits, at a predetermined speed as shown by the revolution indicator, is secured. If the rotor be sufliciently balanced as it comes from the shop, 110 undue vibration will be produced upon rotating it in this apparatus at the predetermined speed and it Will need no further .adjustment. It will be then that with a retor very much unbalanced, the vibration will be stronger, and hence the cushions 12 can be under greater compression than when the rotor is approximately balanced, since a perfectly balanced rotor Would have no vibrationand exertno lateral force on the Patent Office.

[SEAL] bearings Whatever, even though they were free to vibrate.

From the foregoing description, it willbe seen that according to'the method of this invention, the rotor or Whatever body is to be balanced is mounted so as to permit a bodily movement .While being rotated, and this bodily movement is utilized for making indications at points of eccentricity. which.

spccts Without departing from the scope of the invention.

H aving thus described my 1nvention,What

I claim as new and desire to secure by Let;

ters Patent, is:

The combination with a pluralityof U- shaped supports having spaced bridge pieces connecting the uprightportions, of a, link on each support held between said bridge pieces and pivoted at the base of the sup port, a separable bearing hanger carried by the end of each link, and ad ustable resilient abutments mounted between the link and the upright portion of each support.

In testimony whereof I aflix my signature, in presence of two Witnesses.

JOHN F. METTEN. Witnesses:

I. ARRo'rr, ROLAND L. HOWE.

It is herebyeertified that-in Letters Patent No. 1,647,677, granted December 17, 1912, upon the application of John'F. Metten, of Philadelphia, Pennsylvania, for an improvement in Apparatus for the Balancing of Rotatable Bodies, errors appear the printed specification requiring correction as follower Page 1, line 103, for the word bolt read deli; and that the saidLettei-s Patent should be read with correction therein that the same may. conform to the record of the case in the Signed and sealed this 3rd day of June, A. 1)., 1913.

O. C. BILLINGS.

Acting Coimnrissilmcr of Patents.

Section in Letters Patent No. 1,047,677.

shaft is marked at points of eccentricity.

The point upon the shaft at which the mark is made at ordinary speeds is approximately in the radius containing the excess Weight which causes the vibration. The unbalanced portion having" been thus determined, it.

will be apparent that the condition of balance may be approached by removing Weight from the rotor upon the side of the axis Where the mark is located, or by increasing the weight upon the opposite side, either operation tending to "shift the dynamic center of mass closer to the axis of rotation. \Vhen they are coincident balance is of course attained. W eight having been added or subtracted as described, the rotor is again rotated in the movable supports and any vibration produced is availed of as before described tor securing another indication of where weight should be added or removed. This operation is repeated until no vibration, or one within'permissible limits, at a predetermined speed as shown by the revolution indicator, is secured. If the rotor be sufliciently balanced as it comes from the shop, 110 undue vibration will be produced upon rotating it in this apparatus at the predetermined speed and it Will need no further .adjustment. It will be then that with a retor very much unbalanced, the vibration will be stronger, and hence the cushions 12 can be under greater compression than when the rotor is approximately balanced, since a perfectly balanced rotor Would have no vibrationand exertno lateral force on the Patent Office.

[SEAL] bearings Whatever, even though they were free to vibrate.

From the foregoing description, it willbe seen that according to'the method of this invention, the rotor or Whatever body is to be balanced is mounted so as to permit a bodily movement .While being rotated, and this bodily movement is utilized for making indications at points of eccentricity. which.

spccts Without departing from the scope of the invention.

H aving thus described my 1nvention,What

I claim as new and desire to secure by Let;

ters Patent, is:

The combination with a pluralityof U- shaped supports having spaced bridge pieces connecting the uprightportions, of a, link on each support held between said bridge pieces and pivoted at the base of the sup port, a separable bearing hanger carried by the end of each link, and ad ustable resilient abutments mounted between the link and the upright portion of each support.

In testimony whereof I aflix my signature, in presence of two Witnesses.

JOHN F. METTEN. Witnesses:

I. ARRo'rr, ROLAND L. HOWE.

It is herebyeertified that-in Letters Patent No. 1,647,677, granted December 17, 1912, upon the application of John'F. Metten, of Philadelphia, Pennsylvania, for an improvement in Apparatus for the Balancing of Rotatable Bodies, errors appear the printed specification requiring correction as follower Page 1, line 103, for the word bolt read deli; and that the saidLettei-s Patent should be read with correction therein that the same may. conform to the record of the case in the Signed and sealed this 3rd day of June, A. 1)., 1913.

O. C. BILLINGS.

Acting Coimnrissilmcr of Patents. 

